They began in 1987, and Bei Dao has been on the move ever since. He travels with ease through the restless Chinese cultural circles that have sprung up abroad, but he also moves with an unusual comfort through New York, Paris and Prague. And he carries in his pocket something that serves him well: humor. In New York City, he observes that few New Yorkers are religious. “This has something to do with the elevators . . . ascending into the sky and then plunging down through the earth, it is almost impossible to have any sense of the mysteries of heaven or the underworld.” Like many an exile, he is alert and observant, aware of a Parisian night as cool as water, or the sound of a weed growing from a medieval Czech town wall, rustling in the wind. (He hears Kafka’s bones clacking in the same wind.) His eye may pause on something political. Ramallah’s bustling poverty reminds him of towns in China and South Africa; traveling companion Breyten Breytenbach finds Israeli officials there even more efficient in imposing “the greatest difficulty on . . . people’s lives” than the enforcers of apartheid were in his native South Africa. Even when Bei Dao is making one of his more eccentric observations (“Y sneezed twice in my face. He was exhausted from photographing purses”), he never exudes whimsy. His prose is quick on its feet but has a very specific gravity, aware as it is of life’s precariousness. Certainly part of the great pleasure of reading Bei Dao comes from his ability to shift smoothly between the historic and the mundane, from Tiananmen Square to mixing concrete in China’s Hebei Province (he settles words into a sentence with the surety he might use to press a brick onto a wall), from a Weather Underground bomb leveling a Greenwich Village townhouse to his daughter asking him to wait on the sidewalk while she tries on some new clothes.